GEOFF VARRALL is Cofounder and Director of RTT Programmes Limited, a provider of technology and business services to the worldwide wireless industry. He regularly delivers strategic technology programs to vendors, operators, and end users in the USA, Europe, and Asia. He has coauthored with Belcher two engineering-level foundational books for what has become the modern wireless industry.

ROGER BELCHER is Cofounder and Director of RTT Programmes Limited. He develops and presents design programs targeted to the worldwide manufacturing and network operator community. He has coauthored with Varrall two engineering-level foundational books for what has become the modern wireless industry.